Visit us at

Diatoms of the United States is now known as Diatoms of North America.
This site has been redesigned and updated, and will be closing soon.

Biremis circumtexta

(F.Meister ex Hust.) Lange-Bert. and Witkowski in Witkowski, Lange-Bert. and Metzeltin 2000      Category: Symmetrical biraphid
BASIONYM: Navicula circumtexta F.Meister ex Hust. in A.Schmidt et al. 1934

Bacillaria paradoxa


Biremis undulata

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - October 2011
Length Range: 26-36 µm
Width Range: 6.0-7.1 µm
Striae in 10 µm: 16-18


Valves are lanceolate with slightly protracted apices. Raphe is straight with proximal ends slightly expanded and deflected to the primary side. Striae are marginal, forming a wide, lanceolate axial area. Each marginal stria consists of four areolae, which are easily observed under LM. There is also a longitudinal row of areolae adjacent to the raphe slits on the primary side of the valve. Externally, a thin conopeum extends from the valve margin and covers the areolae, except those those areolae adjacent to the axial area. The conopeum can be observed only under SEM, but under LM, its margin is visible as a longitudinal line crossing the striae. The striae are slightly radiate in the valve center, becoming parallel near the apices.

Original Description

Basionym: Navicula circumtexta
Author: F.Meister ex Hust. in A.Schmidt et al. 1934
Length Range: µm
Striae in 10 µm:

Original Description

Kiang Wau, Ostasien. Navicula circumtexta Meister, nov. spec. Die mittlere, von den Längslinien eingefaβte Schalenpartie lieft höher als die Randzone.

Original Images

Cite This Page:
Potapova, M. (2011). Biremis circumtexta . In Diatoms of the United States. Retrieved May 22, 2018, from

Species: Biremis circumtexta

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


Patrick, R.M. and Reimer, C.W. (1966). The Diatoms of the United States exclusive of Alaska and Hawaii, V. 1. Monographs of the Academy of Natural Sciences of Philadelphia 13.

Schmidt, A. (-). (1874-1959). Atlas der Diatomaceen-Kunde, von Adolf Schmidt, continued by Martin Schmidt, Friedrich Fricke, Heinrich Heiden, Otto Muller, Friedrich Hustedt. Reprint 1984, Koeltz Scientific Books, Konigstein, 480 plates.

Witkowski, A., Lange-Bertalot, H. and Metzeltin, D. (2000). Diatom Flora of Marine Coasts I. Iconographia Diatomologica 7: 1-925.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

Biremis circumtexta CAS

North American Diatom Ecological Database (NADED)

NADED ID: 206001

Autecology Discussion

Biremis corcumtexta is usually found in inland waters of high mineral content or in coastal habitats

EMAP Assessment

The Environmental Protection Agency (EPA) western Environmental Monitoring and Assessment Program (EMAP) study was completed during the years 2000-2004 (see citations at bottom of this page). Over 1200 streams and rivers in 12 western states (Arizona, California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming) were selected for sampling based on a stratified randomized design. This type of design insures that ecological resources are sampled in proportion to their actual geographical presence. Stratified randomized design also allows for estimates of stream length with a known confidence in several “condition classes” (good or least-disturbed, intermediately-disturbed, and poor or most-disturbed) for biotic condition, chemistry and habitat.

EMAP Distribution

Biremis circumtexta

EMAP Response Plots

Biremis circumtexta

EMAP citations

Results are published in:

Johnson, T., Hermann, K., Spaulding, S., Beyea, B., Theel, C., Sada, R., Bollman, W., Bowman, J., Larsen, A., Vining, K., Ostermiller, J., Petersen, D. Hargett, E. and Zumberge, J. (2009). An ecological assessment of USEPA Region 8 streams and rivers. U.S. Environmental Protection Agency Region 8 Report, 178 p.

Stoddard, J. L., Peck, D. V., Olsen, A. R., Larsen, D. P., Van Sickle, J., Hawkins, C. P., Hughes, R. M., Whittier, T. R., Lomnicky, G. A., Herlihy, A. T., Kaufman, P. R., Peterson, S. A., Ringold, P. L., Paulsen, S. G., and Blair, R. (2005). Environmental Monitoring and Assessment Program (EMAP) western streams and rivers statistical summary. U.S. Environmental Protection Agency Report 620/R-05/006, 1,762 p.

Stoddard, J. L., Peck, D. V., Paulsen, S. G., Van Sickle, J., Hawkins, C. P., Herlihy, A. T., Hughes, R. M., Kaufman, P. R., Larsen, D. P., Lomnicky, G. A., Olsen, A. R., Peterson, S. A., Ringold, P. L., and Whittier, T. R. (2005). An ecological assessment of western streams and rivers. U.S. Environmental Protection Agency Report 620/R-05/005, 49 p.